Method for humerus retraction

ABSTRACT

A method for performing surgery on a shoulder joint utilizes one positionable support arm attached to a retractor support apparatus. The method includes incising a patient to expose the shoulder joint. After exposing the shoulder joint, the humeral ball is dislocated from the glenoid cavity. A retractor is mounted to one of the support arms at a proximal end. A humerus retractor blade at a distal end of the humerus retractor engages the humerus. The humerus retractor blade is positioned about the humerus and a mechanical system within the humerus retractor is manipulated to laterally displace the humeral ball from the glenoid cavity.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application is a continuation-in-part of U.S. applicationSer. No. 09/654,400 filed on Sep. 1, 2000, now U.S. Pat. No. 6,315,718,and claims priority therefrom.

BACKGROUND OF THE INVENTION

The present invention relates to a method of surgical retraction. Inparticular, the present invention relates to a method of retracting thehumerus during shoulder surgery.

Total shoulder replacement (arthroplasty) operations have been performedfor many decades to repair shoulder components. These components includethe glenoid cavity (socket portion of the shoulder) and the humeral head(ball portion of the shoulder). The shoulder is typically replaced dueto a gradual deterioration or wearing of the glenoid cavity and/or thehumeral head or ball. Common causes of the deterioration of the shoulderjoint from smooth surfaces where the joint is properly articulating torough surfaces where articulation of the joint is painful includeosteoarthritis, Rheumatoid arthritis as well as trauma which injures theshoulder joint. The deterioration causes either the humeral ball, theglenoid cavity or both the humeral ball and the glenoid cavity becomerough which results in pain when the shoulder joint is articulated.

Surgical procedures have been the most successful method to alleviatethis type of shoulder pain. Either partial or total shoulder replacementsurgery can be performed. In a total shoulder replacement procedure, acup shaped insert, typically manufactured of polyethylene, is insertedinto the worn glenoid cavity and a metal ball is used to replace thehumeral head. A partial shoulder replacement is performed when eitherthe humeral ball is replaced or the glenoid cavity is repaired with aninsert.

The shoulder replacement surgery is conducted by making an incisionthrough the skin into the front of the shoulder. Typically, the incisionis about three inches long. Because of the relatively small size of theincision and the surgical site being on one side of the body, access tothe surgical site is limited.

After making the incision through the skin, the surgeon divides thetissue and muscle to expose the shoulder joint. When the humeral ball isreplaced, the surgeon separates the humeral bone from the humerus,typically with a bone saw. The surgeon has two options when separatingthe humeral ball from the humerus. The humeral ball may be separatedfrom the humerus while the humeral ball remains within the glenoidcavity. Alternatively, the humeral ball may be dislocated from theglenoid cavity followed by the humeral ball being separated from thehumerus.

After separating the humeral ball from the humerus, the arm is retractedaway from the body, or laterally. The arm is usually retracted with ahand-held retractor where the surgeon or an assistant must apply aconstant force upon the humerus. One hand-held retractor that is usedfor retracting the humerus is called a Fakuda blade. A Fakuda blade hasa flat surface with a curved end. An aperture is disposed within theFakuda blade which better grips the humerus than a blade having only aflat surface.

After laterally retracting the humerus, the humeral ball is dislocatedfrom the glenoid cavity, thereby exposing the glenoid cavity forinsertion of the cup shaped insert. Additionally, laterally retractingthe humerus away from the shoulder joint makes the freshly cut portionof the humerus accessible for replacement of the humeral ball.

The humerus is prepared by hollowing a cavity into the interior of thehumerus with a rasp to create a place for the humeral ball component tobe attached to the humerus. The metal humeral ball includes a stem whichis inserted into the hollowed out cavity in the humerus. The metalhumeral ball is fixedly attached to the humerus by techniques which areknown in the art including, but not limited to, cement or a non-cementtechnique, such as bony ingrowth.

Typically, at least two strong people are needed to perform a totalshoulder replacement. One person is needed to retract the humerus fromthe glenoid cavity to gain access to both the glenoid cavity and thehumerus. The other person is needed to prepare the glenoid cavity andthe humerus for the insert and metal ball, respectively. After thereplacement components are inserted, the shoulder is reduced (thehumeral component is inserted into the glenoid cavity component) tocheck the angle and fit of the humeral ball into the glenoid cavityinsert. If the shoulder components do not adequately fit, the shoulderis again dislocated, the components readjusted, and the humeral ball ispositioned in the glenoid cavity . If the stability and placement of thetrial inserts is acceptable, the shoulder is dislocated and the humeralimplant stem is placed into and secured within the hollowed cavity ofthe humerus. The humeral ball is again positioned within the glenoidcavity and the stability of the arthroplasty is confirmed.

Due to the multiple dislocations and insertions of the humeral ball intothe glenoid cavity, as well as retracting the humerus, the surgicalprocedure can become quite physically taxing on the surgeon or surgeonsperforming it. The surgical procedure requires lifting and moving thepatient's arm into multiple positions. At times, the surgeon may need tohold the arm in a selected position for an extended period of time.Depending on the size of the patient, the strenuous activity can lead tofatigue and contribute to surgical error. Additionally, the repeatedmovement of the arm can cause nerve damage if it is not done preciselyand with minimal adjustment. When the surgeon moves the humerus by handit is common to have continual adjusting occur. Often, the surgeonholding the arm, relaxes or becomes fatigued and allows the arm to move,requiring that the arm be readjusted. The movement can cause the arm topinch or rub nerves or muscle tissue, possibly causing damage.

BRIEF SUMMARY OF THE INVENTION

The present invention includes a method for performing surgery on ashoulder joint using at least one positionable support arm attached to aretractor support apparatus, where the shoulder joint includes a glenoidcavity, a humerus and a humeral ball attached to the humerus andpositioned within the glenoid cavity. The method includes incising apatient to expose the shoulder joint. After exposing the shoulder joint,the humeral ball is dislocated from the glenoid cavity. A retractor ismounted to one of the support arms at a proximal end. A humerusretractor blade at a distal end of the retractor engages the humerus.The humerus retractor blade is positioned about the humerus and amechanical system within the humerus retractor is manipulated tolaterally displace the humeral ball from the glenoid cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a support structure for a shouldersurgery.

FIG. 2 is a perspective view of a retractor mechanism having anarticulated joint for adjusting a height of a retractor blade.

FIG. 3 is a perspective view of a retractor mechanism having amechanical system for adjusting a longitudinal position of a retractorblade.

FIG. 4 is a perspective view of the support members for a shoulderoperation.

FIG. 5 is a partial perspective view of a humerus being longitudinallyretracted from the glenoid cavity with a retractor blade having anaperture therein.

FIG. 6 is an exploded view of the retractor mechanism of the presentinvention.

FIG. 7 is a partial perspective view of a mechanism for attaching aretractor blade to the retractor mechanism.

DETAILED DESCRIPTION

The present invention relates to a method for retracting the upper armor humerus bone during a shoulder surgery as generally illustrated inFIG. 1 at 10. In preparation for a shoulder replacement surgery, aheight of a generally J-shaped member 16 is adjusted by clamping thesupport member 14 in a selected position on a retractor supportapparatus 12 with a clamp 13.

To provide adequate support around the shoulder while maintaining accessto the shoulder to be operated upon, the generally J-shaped member 16 isattached to the support member 14 as illustrated in FIG. 1. Thegenerally J-shaped member 16 includes an arcuate portion 18 proximate afirst end 19, a substantially straight middle portion 20 and anoutwardly extending portion 22 proximate a second end 21. An engagingportion 24 which engages the support member 14 is positionedsubstantially perpendicular to the outwardly extending portion 22. Theengaging portion 24 is designed to engage the docking member disclosedin U.S. application Ser. No. 09/654,400 from which this application is acontinuation-in-part and which is hereby incorporated by reference inits entirety.

Referring to FIGS. 1 and 4, the generally J-shaped member 16 includessubstantially uniformly spaced apart apertures 26 along the arcuateportion 18 proximate a first end 19 and also the substantially straightmiddle portion 20. A T-shaped member 28 having a plurality of apertures30 along the long portion 32 of the T-shaped member 28 is operablyattached to the generally J-shaped member 16. The T-shaped member 28includes first and second pegs 36, 38 proximate first and second ends40, 42, respectively, of a short portion 34, as illustrated in FIG. 4.The first and second pegs 36, 38 engage the uniformly spaced apartapertures 26 in the generally J-shaped member 16 such that the T-shapedmember 28 is positionable along the generally J-shaped member 16.

Referring to FIGS. 1 and 5, the surgical procedure begins by adjustingthe height of the support structure 14. The generally J-shaped member 16is rotatably positioned about a shoulder 40 to be surgically repaired.The first and second pegs 36, 38 of the T-shaped member 28 arepositioned in a selected position within the plurality of apertures 26in the generally J-shaped member 16. The combination of the generallyJ-shaped member 16 and the T-shaped member 28 provide the requiredsupport structure for performing the operation while maintaining accessto the surgical site. The selected location of the T-shaped member 28 isdetermined by the type of surgical procedure to be performed, the sizeof the incision to be made and the size of the patient being operatedupon.

Referring to FIG. 5, an incision 13 is made into the flesh of thepatient. Retractors 44, 46, as best illustrated in FIG. 2, are securedto both the generally J-shaped member 16 and the T-shaped member 28 andretract the flesh from the incision 13 thereby exposing the shoulderjoint 40. With the shoulder joint 40 exposed, the glenoid cavity 41, thehumeral ball 43 and an upper portion of the humerus 45 are viewablethrough the retracted incision 13.

Referring to FIGS. 1, 5 and 6, a retractor mechanism 50 is securelypositioned on the generally J-shaped member 16 by a cooperation of a pin52 extending downwardly from a bottom surface 54 of a gearbox assembly56 with one of the apertures 26 within the generally J-shaped member 16.The pin 52 is in a perpendicular relationship with the bottom surface 54and extends through a thickness of the generally J-shaped member 16.Preferably, the thickness of the generally J-shaped member 16 is ¼″ andthe pin 52 is ¾″ in length. An end of the pin 52 extends approximately ½inch below the bottom surface of the generally J-shaped member 16. Theexcess length of the pin 52 prevents the retractor mechanism 50 fromrotating off of the generally J-shaped member 16 when a force is appliedto a retractor blade 44, 46 or 200. The only method of removing theretractor mechanism 50 from the generally J-shaped member 16 is to liftthe gearbox assembly 56 away from atop surface of the generally J-shapedmember 16 until the pin 52 disengages the aperture 26 within thegenerally J-shaped member 16. While the pin 52 is disposed within theaperture 26, the retractor mechanism 50 is pivotally attached to thegenerally J-shaped member 16.

The gearbox assembly 56 includes a gearbox casing 58 attached to anouter casing 60. The outer casing 60 is preferably U-shaped and includesthe bottom surface 54 to which the pin 52 is attached, a top surface 62and a first side surface 64. The gearbox casing 58 includes first andsecond shoulders 66,68 which contact a first end 59 and a second end 61of the outer casing 60. The shoulders 66, 68 are designed such that eachshoulder is even with the top and bottom surfaces 62, 54, when thegearbox casing 58 engages the outer casing 60.

The gearbox casing 58 extends within the outer casing 60 such that afirst surface 70 of the gearbox casing 58 and the top surface 62, thebottom surface 54 and the first side wall 64 defme a retractor handlebore 66. The retractor handle bore 66 is preferably substantiallyrectangular in configuration, although other cross-sectionalconfigurations are within the scope of the invention. The retractorhandle bore 66 is positioned proximate a second side 67 of the gearboxassembly 56.

A channel 71 is disposed along a length of the first surface 70 of thegearbox casing 58. A pawl retaining cavity 72 is machined into thechannel 71 proximate a second end 80 of the gearbox assembly 56. Thepawl retaining cavity 72 extends to an outer surface of the gearboxcasing 58.

A gear bore 74 is positioned proximate a first side 76 and a first end78 of the gearbox assembly 56. The gear bore 74 is in a substantiallyorthogonal relationship with the retractor handle bore 66. The gear bore74 is in communication with the retractor handle bore 66.

A pawl 82 is inserted into the pawl retaining cavity 72 and retainedwithin the cavity 72 by a cooperation of a pin 84 being inserted into anaperture 86 within the top surface 62, a bore (not shown) which extendsinto the pawl retaining cavity 72 and a bore 81 through the pawl 82which is aligned with the bore (not shown) in the gearbox casing 58.Additionally, a bore (not shown) may continue through the pawl retainingcavity 72 to secure an end of the pin 84 within a non-moving part. Thepin 84 has an engaging portion 86 proximate a head 88 which creates africtional engagement of the pin 84 with the bore (not shown) within thegearbox casing 58, thereby retaining the pin 84 within the gearboxassembly 56 and the pawl 82 within the pawl retaining cavity 72.

A retractor handle 90 is disposed through the retractor handle bore 66.The retractor handle 90 is preferably a three sided channel 93 whichcooperates with the rectangular retractor handle bore 66. Extending froma first side 92 of the retractor handle is a rack (not shown) of a rackand pinion system (not shown). When the retractor handle 90 is disposedwithin the retractor handle bore 66, the rack (not shown) extends withinthe channel 71 of the retractor handle bore 66.

A gear pin 94 is inserted into the gear bore 74 from the top surface ofthe outer casing 60. A gear 96, having pinions 98 disposed annularlyaround a circumference of the gear pin 94, is disposed within the gearbore 74 such that the pinions 98 extend into the channel 71 and engagegrooves which define the rack (not shown). The gear pin 94 has a bore(not shown) extending from an end which is aligned about a central axisof the gear pin 94. A retaining pin 100 is inserted through an aperture(not shown) within the bottom surface of the outer casing 60 alignedwith the bore (not shown) within the gear pin 94 when the gear pin 94 iswithin the gear bore 74. The retaining pin 100 includes an engagingportion 99 with a slightly larger diameter than the pin which securesthe pin 100 within the bore (not shown) of the gear pin 94 therebysecuring the gear pin 94 within the gear bore 74.

A length of the rack (not shown) determines the maximum distance thatthe retractor handle 90 can be moved through the retractor bore 66 bythe manipulation of the rack and pinion system (not shown). The surgeonis easily able to manipulate the position of a retractor blade 21 byrotating the gear pin 94 which in turn rotates the pinions 98 of thegear 96. The interaction of the rotating pinions 98 with the rack (notshown) causes the retractor handle 90 to move longitudinally withrespect to the retractor handle bore 66 thereby allowing the surgeon tomove the retractor blade 21 laterally into a desired position as bestillustrated in FIG. 3.

Referring back to FIG. 6, the pawl 82, which is pivotally attached tothe gearbox casing 58 by the pin 84, includes a notch 102 proximate afirst end 101. The notch 102 includes a substantially right corner whichengages the pinions 98 of the gear 96 such that the gear 96 cannot berotated in a reverse direction without first displacing the notch 102from the pinions 98 of the gear 96. The pawl 82 is biased to engage thenotch 102 with the pinions by a compression spring 104 engaging ashoulder 106. The spring 104 biases a second end 103 toward an outeredge of the gearbox casing 58 such that the second end 103 extends pastthe edge of the gear box casing 58. While the second end 103 of the pawl82 is biased toward the edge, the first end 101 is biased toward thepinions 98. The pawl 102 prevents accidental movement of the retractorhandle 90 when the rack and pinion system (not shown) applies a force tothe humerus 45 and laterally retracts the humeral ball 43 from theglenoid cavity 41. A length of a surface 108 proximate the second end103 of the pawl 82 prevents the second end 103 from engaging the groovesdefining the rack (not shown).

Referring to FIG. 2, an articulated joint 110 allows the retractor blade200 to be raised or lowered relative to a blade end 91 of the retractorhandle 90 by a pivot pin 112. Referring back to FIG. 6, the retractorhandle 90 has a rectangular channel 93 disposed through a length of theretractor handle extending from the blade end 91 to a handle end 89.

A push rod 114 extends through the length of the channel 93 within theretractor handle 91. A first end 113 of the push rod 114 is disposedthrough an aperture at the handle end 89 of the retractor handle 90. Afirst shoulder 116 proximate the first end 113 contacts the aperture,thereby fixing the push rod 114 in a selected position with respect tothe retractor handle 90 while maintaining rotatability of the push rod114. A washer 118 is disposed over the first end 113 of the push rod 114and a knob 116 is fixedly attached to the first end 113 of the push rod114. The washer 118 prevents the handle end 89 of the retractor handle90 from goring a surface of the knob 116 and binding the knob 116 to thehandle end 89 of the retractor handle 90.

Intermediate the first end 113 and a second end 115 of the push rod 114is a center portion 120 defining a second shoulder 122 and a thirdshoulder 124. The center portion 120 has a larger diameter than thediameter of portions adjacent to the center portion 120. The differencesin the diameters define the second and third shoulders 122, 124. Aspacer 126 is disposed over the second end 115 of the push rod 114. Thesecond end 115 of the push rod 114 is threaded and threadably engages athreaded bore (not shown) within a first end 130 of a first wedge 128.

The first wedge 128 has a substantially rectangular cross-sectionproximate the first end 130. The rectangular cross-sectional portion ofthe first wedge 128 cooperates with the rectangular channel 93 withinthe retractor handle 90 which prevents the first wedge 128 from rotatingwithin the rectangular channel 93. Because the first wedge 128 does notrotate when the push rod 114 is rotated, the threadable engagement ofthe push rod 114 with the bore (not shown) within the first wedge 128causes the first wedge 128 to move relative to the second end 115 of thepush rod 114 when the push rod 114 is rotated. A first wedge surface 134is defined by a flat surface extending from a top surface 136 to an edgeat the bottom surface 138 at a second end 132.

A mounting member 140 includes a bore 142 which aligns with first andsecond apertures 95, 97 within the first side and a second sides of theretractor handle 90. A pivot pin 144 is inserted through the firstaperture 95, the through bore 142 and the second aperture 97 therebypivotally attaching the mounting member 140 to the retractor handle 90.

Proximate a first end 141 of the mounting member 140 is a second wedgesurface 146. The second wedge surface 146 extends from a top surface 148intermediate the first end 141 and a second end 143 to a bottom surface150 proximate the first end 141. An angled surface 152 extends upwardlyat a slant from the bottom surface 150 toward the first end 141 suchthat the first end 141 of the mounting member 140 is defined by an edgeabove the bottom surface 150.

As the push rod 114 is rotated, the second end 132 of the first wedgesurface 134 engages the angled surface 152 of the mounting member 140.Further movement of the first wedge surface 134 toward the mountingmember 140 causes the mounting member 140 to pivot about the pivot pin144 while the angled surface 152 travels up the first wedge surface 134.The second wedge surface 146 has a circular recess 154 which cooperateswith a compression spring 156. An end of the compression spring 156rests on a substantially flat, bottom surface of the circular recess154. Another end of the compression spring 156 is positioned against aninner surface of a top portion 85 of the retractor handle 90.

As the angled surface 152 travels up the first wedge surface 134, thecompression spring 156 compresses which biases the angled surface 152 totravel down the first wedge surface 134 as the first wedge 128 ismanipulated away from the mounting member 140. One skilled in the artwill realize that the second wedge surface 146 allows for greaterpivotal movement of the mounting member 140 because the first end 141 ofthe mounting member 140 will not contact the top portion 85 of theretractor handle 90 until the second wedge surface 146 contacts the topportion 85. One skilled in the art will also recognize that because themounting member 140 is pivotally attached to the retractor handle 90between the first end 141 and a second end 143 that as the first end 141is raised the second end 143 is lowered and vice versa.

Referring to FIG. 7, a cylindrical portion 160 extends from the mountingmember 140. A through bore 161 is disposed through the cylindricalportion 160 proximate the second end 143 of the mounting member 140. Ashoulder 164 is defined proximate an end of the cylindrical portion 160.

A plug 166 having a bore 168 extending from a first end 170 to a secondend 171 is disposed over the cylindrical portion 160 of the mountingmember 140 until the first end 170 is adjacent to the shoulder 164. Withthe first end 170 of the plug adjacent to the shoulder 164, a first slot172 within a first side surface 176 of a rectangular body 175 and asecond slot 174 within a second side surface 178 of the rectangular body175 are aligned with the through bore 161 within the cylindrical portion160.

A pin 180 is inserted through the first slot 172, the through bore 161and the second slot 174. An end of the pin 180 is substantially evenwith an outer surface of the first side surface 176 and another end ofthe pin 180 is substantially even with an outer surface of the secondside surface 178. Neither end of the pin 180 extends past the outersurfaces of the first and second side surfaces 176, 178. The slots 172,174 are wider than the diameter of the pin 180 allowing the plug 166 topartially rotate about the cylindrical portion 160 until the pin 180contacts either surface of the slots 172, 174. Preferably, the plug 166rotates 10 to 20 degrees about the cylindrical portion 160.

A retractor engaging member 182 having a rectangular bore (not shown)extending from a first end 183 cooperates with the rectangular body 175of the plug 166. The cooperation of the rectangular body 175 with therectangular bore (not shown) prevents rotation of the retractor engagingmember 182 about the plug 166. The retractor engaging member 182 isslidably positioned on the plug 166 until the first end 181 of theretractor engaging member 182 contacts a shoulder 177 about the plug166. The outer surface around a perimeter of the shoulder 177 is evenwith the rectangular outer surface of the retractor engaging member 182.

Proximate a second end 185 of the retractor engaging member 182 is thethrough bore 162. Extending from an end 201 of a retractor blade 200 isa cylindrical member 202 which cooperates with the through bore 162. Thecooperation of the cylindrical member 202 with the through bore 186allows the retractor blade 200 to rotate about the cylindrical member202 while being retained therein.

Referring to FIG. 5, the present invention includes the humerusretractor blade 200 attachable to the retractor mechanism 50 by thecooperation of the cylindrical member 202 attached to the blade 200 withthe through bore 162 in the retractor blade engaging member 182. Thehumerus retractor blade 200 resembles a Fakuda blade having a generallyflat portion 204 with an arcuate end portion 206 and an aperture 208disposed within the generally flat portion 204 and extending into thearcuate end portion 206. The aperture 208 in the humerus retractor blade200 is used to better grip bone and flesh at the surgical site.

Prior to making an incision, the generally J-shaped member 16 and theT-shaped member 28 are adjusted to desired positions by the surgeon.After an incision 13 has been made, the flesh is retracted to expose theshoulder joint 40 by standard retractor blades 44, 46 which are wellknown in the art. After exposing the shoulder joint 40, the retractingmechanism 50, to which the humerus retractor blade 200 is attached, ispositioned in a desired location by inserting the pin 52 extending fromthe bottom surface 54 of the gearbox assembly 56 into an aperture 26within the generally J-shaped member 16.

After positioning the retracting mechanism 50 in the desired aperture26, the gear pin 94 is manipulated to position the humerus retractorblade 200 medially beyond the humerus 45 proximate the humeral head 43by rotating the gear pin 94. The rotation of the gear pin 94 causes thepinions 98 of the gear 96 to engage the rack (not shown) attached to theretractor handle 90 which causes the retractor handle 90 and the humerusretractor blade 200 to move toward the humerus 45. Once the humerusretractor blade 200 is positioned on a medial side (body side) of thehumerus 45 proximate the humeral ball 43, the height of the retractorblade 200 is adjusted.

The height of the humerus retractor blade 200 is adjusted bymanipulating the articulated joint 110 by rotating the knob 116proximate the handle end 89 of the retractor handle 90 as illustrated inFIG. 2. Rotating the knob 116 causes the first wedge 128 to engage theangled surface 152 of the mounting member 140 causing the first end 141of the mounting member 140 to rise up the first wedge 128. As the firstend 141 rises up the first wedge 128, the second end 143 of the mountingmember 140 pivots downward about the pin 144. The second end 143 ispivoted downward until the arcuate end 206 of the humerus retractorblade 200 is positioned about the humerus 45 on a medial side of thehumerus 45. The position of the humerus retractor blade 200 can beslightly adjusted by rotating the retractor engaging member 182 aboutthe cylindrical portion 160 of the mounting member 140.

With the arcuate end portion 206 of the humerus retractor blade 200 inthe desired location, the gear pin 94 is rotated in an oppositedirection thereby causing the mechanical system, preferably but notlimited to a rack and pinion system (not shown), to move the retractorhandle 90 and the humerus retractor blade 200 laterally, as illustratedin FIG. 3, away from the shoulder joint 40. The humerus retractor blade200 is used to retract the humerus 45 after separation from the humeralball 43 or after the humeral ball 43 is dislocated from the glenoidcavity 41 but prior to being separated from the humerus 45. As theretractor blade 200 is moved away from the shoulder joint 40 by the rackand pinion system (not shown), a lateral force is applied to the humerus45 until the humerus 45 is displaced a desired distance from the glenoidcavity 41. With the humeral ball 43 displaced from the glenoid cavity41, the humeral ball 43 is replaced and an insert is disposed within theglenoid cavity 41 to repair the glenoid cavity 41.

The pawl 82 engages the pinions 98 of the gear 96, preventing theretractor handle 90 from inadvertently moving toward the shoulder joint40 and releasing the force applied by the humerus retractor blade 200.Additionally, the pawl 82 allows the surgeon to rest if needed duringthe surgical procedure without having to reapply the force alreadyexerted upon the humerus 45.

The use of the mechanically adjustable retractor mechanism 50 allows thehumerus 45 to be displaced from the glenoid cavity 41 using a minimumamount of force and a minimum amount of movement as necessary to performthe shoulder replacement surgery. Using only the required force andminimizing movement reduces the amount of trauma to the patient andreduces the amount of time required to recover.

Additionally, the use of the humerus retractor blade 200 along with theretractor mechanism 50 to laterally retract the humerus 45 from theglenoid cavity 41 reduces the number of surgeons required to perform thesurgical procedure. The reduction in personnel required to perform thesurgery is possible because a surgeon is not needed to provide a forceto displace the humerus 45 laterally from the glenoid cavity 41. Rather,the rack and pinion system (not shown) is used in the place ofadditional surgical personnel which provides the surgeon with betteraccess to the limited surgical site.

Once the necessary procedures have been performed on the glenoid cavity41 and the humerus 45, the pawl 82 is disengaged from the gear pinions98 and the rotation of the gear pin 94 is reversed to manipulate therack and pinion system (not shown) which, in turn, positions the humeralball 43 proximate the glenoid cavity 41. With the humeral ball 43proximate the glenoid cavity 41, the humerus retractor blade 200 isdisengaged from the humerus 45. Once the humerus retractor blade 200disengages the humerus 45, the surgeon raises the pin 52 from theaperture 26 thereby removing the retractor mechanism 50 from thesurgical site. With the implanted humeral ball 43 adjacent to therepaired glenoid cavity 41, the surgeon forces the humeral ball 43 intothe surgically repaired glenoid cavity 41.

Although the present invention has been described with reference topreferred embodiments, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the invention.

What is claimed is:
 1. A method of performing surgery on a shoulderjoint using at least one support arm attached to a retractor supportapparatus, the shoulder joint includes a glenoid cavity, a humerus and ahumeral ball attached to the humerus and positioned within the glenoidcavity, the method comprising: incising a patient to expose the shoulderjoint; dislocating the humeral ball from the glenoid cavity; mounting aproximal end of a humerus retractor on the one support arm wherein thehumerus retractor comprises a humerus retractor blade at a distal end;positioning the humerus retractor about the humerus; and retracting thehumeral ball laterally away from the glenoid cavity with a mechanicalmechanism of the humerus retractor thereby providing access to theglenoid cavity and the humeral ball.
 2. The method of claim 1 andfurther comprising separating the humeral ball from the humerus.
 3. Themethod of claim 2 and further comprising sawing the humeral ball fromthe humerus.
 4. The method of claim 2 and further comprising: hollowinga cavity into a freshly separated surface of the humerus; disposing astem having a ball attached thereto into the cavity in the humerus; andsecuring the stem within the cavity such that the ball is fixed intoposition on the humerus.
 5. The method of claim 4 and further comprisingsecuring an insert within the glenoid cavity.
 6. The method of claim 5and further comprising disposing the ball attached to the humerus withinthe insert secured within the glenoid cavity.
 7. The method of claim 2wherein the positioning of the humerus retractor further comprises:manipulating the mechanical system, wherein the mechanical systemcomprises a rack and pinion system, to adjust a longitudinal position ofthe humerus retractor blade such that the humerus retractor blade,including a substantially flat portion, an arcuate end portion and anaperture therein, extends beyond a medial surface of the humerus;manipulating a vertical adjustment system, wherein the verticaladjustment system comprises an articulated joint, to lower the arcuateend portion of the humerus retractor blade below the humerus such thatthe aperture within the humerus retractor blade is vertically alignedwith the humerus; and manipulating the rack and pinion system of themechanical system such that the humerus retractor blade including theaperture engages the humerus.
 8. The method of claim 7 wherein thelateral retraction of the humerus from the glenoid cavity furthercomprises manipulating the rack and pinion system of the mechanicalsystem to displace the humeral head from the glenoid cavity to provideaccess thereto.
 9. The method of claim 8 and further comprising:disengaging a pawl from the rack and pinion system; and manipulating therack and pinion system such that the humeral ball attached to thehumerus is positioned proximate the glenoid cavity.
 10. The method ofclaim 9 and further comprising: manipulating the articulated joint suchthat the humeral ball is juxtaposed to the glenoid cavity; andmanipulating the rack and pinion system to disengage the humerusretractor blade from the humerus.
 11. The method of claim 10 and furthercomprising inserting the humeral ball within the glenoid cavity.
 12. Themethod of claim 1 and wherein the positioning of the support armcomprises: disposing a generally J-shaped support arm within a retractorsupport mounted to a surgical table; and disposing a T-shaped memberhaving a plurality of pegs extending downward into a plurality ofapertures within the generally J-shaped support arm wherein the T-shapedmember and generally J-shaped support arm provides access to thesurgical site.
 13. A method of minimizing a force required to prepare ashoulder joint for a shoulder surgery, the shoulder joint including aglenoid cavity, a humerus, and a humeral ball attached to the humeruswherein the humeral ball is disposed within the glenoid cavity, themethod comprising: incising a patient; retracting the incision to exposethe shoulder joint; dislocating the humeral ball from the glenoidcavity; positioning a support arm on a retractor support; operablyconnecting a humerus retractor to the support arm; engaging the humeruswith the humerus retractor; and applying a force to the humerus with amechanical system of the humerus retractor until the humeral head islaterally displaced a selected distance from the glenoid cavity therebyproviding access to the glenoid cavity and the humeral ball.
 14. Themethod of claim 13 and further comprising separating the humeral ballfrom the humerus.
 15. The method of claim 14 and further comprisingsawing the humeral ball from the humerus.
 16. The method of claim 13 andfurther comprising: hollowing a cavity into a freshly separated surfaceof the humerus; disposing a stem having a ball attached thereto into thecavity in the humerus; and securing the stem within the cavity such thatthe ball is fixed into position on the humerus.
 17. The method of claim16 and further comprising securing an insert within the glenoid cavity.18. The method of claim 17 and further comprising disposing the ballattached to the humerus within the insert secured within the glenoidcavity.
 19. The method of claim 13 wherein the engaging of the humeruswith the humerus retractor further comprises: manipulating themechanical system, wherein the mechanical system comprises a rack andpinion system, to adjust a longitudinal position of the humerusretractor blade, the humerus retractor blade comprising a flat portion,an arcuate distal end and an aperture disposed within the humerusretractor blade, such that the humerus retractor blade extends beyond amedial surface of the humerus; manipulating a vertical adjustmentsystem, wherein the vertical adjustment system comprises an articulatedjoint, to lower the arcuate distal end of the humerus retractor bladebelow the humerus such that the aperture within the humerus retractorblade is vertically aligned with the humerus; and manipulating the rackand pinion system of the mechanical system such that the humerusretractor blade including the aperture engages the humerus.
 20. Themethod of claim 19 wherein the lateral displacement of the humerus fromthe glenoid cavity further comprises manipulating the rack and pinionsystem of the mechanical system to displace the humeral head from theglenoid cavity to provide access thereto.
 21. The method of claim 20 andfurther comprising: disengaging a pawl from the rack and pinion system;and manipulating the rack and pinion system such that the humeral ballattached to the humerus is positioned proximate the glenoid cavity. 22.The method of claim 21 and further comprising: manipulating thearticulated joint such that the humeral ball is juxtaposed to theglenoid cavity; and manipulating the rack and pinion system to disengagethe humerus retractor blade from the humerus.
 23. The method of claim 22and further comprising inserting the humeral ball within the glenoidcavity.
 24. The method of claim 13 and wherein the positioning of thesupport arm comprises: disposing a generally J-shaped support arm withina retractor support mounted to a surgical table; and disposing aT-shaped member having a plurality of pegs extending downward into aplurality of apertures within the generally J-shaped support arm whereinthe T-shaped member and the generally J-shaped support arm provideaccess to the surgical site and support the retractors.
 25. A method ofreducing a number of surgical personnel required to perform a surgicalprocedure on a shoulder joint, the shoulder joint including a glenoidcavity, a humeral ball disposed within the glenoid cavity and a humerusextending from the humeral ball, the method comprising: incising apatient so as to expose the shoulder joint; dislocating the humeral ballfrom the glenoid cavity; positioning a humerus retractor on a support;and manipulating a mechanical system within the humerus retractor suchthat a humerus retracting blade of the humerus retractor engages thehumerus such that a movement of the humerus retractor blade produces aforce which displaces the humeral ball from the glenoid cavity.
 26. Themethod of claim 25 wherein the support includes a generally J-shapedmember and a T-shaped member operably attached to the generally J-shapedmember and further comprising positioning the generally J-shaped memberand the T-shaped member in a selected retracting position.
 27. Themethod of claim 25 and further comprising maintaining the force on thehumerus with a pawl cooperating with the mechanical system comprising arack and pinion system thereby reducing the need for another person tomaintain constant force on the humerus during the surgical procedure.28. The method of claim 25 and further comprising separating the humeralball from the humerus.
 29. The method of claim 28 and farther comprisingsawing the humeral ball from the humerus.
 30. The method of claim 28 andfurther comprising: hollowing a cavity into a freshly separated surfaceof the humerus; disposing a stem having a ball attached thereto into thecavity in the humerus; and securing the stem within the cavity such thatthe ball is fixed into position on the humerus.
 31. The method of claim30 and further comprising securing an insert within the glenoid cavity.32. The method of claim 31 and further comprising: manipulating a rackand pinion system to position the humeral ball proximate the glenoidcavity; and disengaging the humerus retractor from the humerus.
 33. Themethod of claim 32 and further comprising disposing the ball attached tothe humerus within the insert secured within the glenoid cavity.
 34. Amethod of performing a surgical procedure on a shoulder joint, theshoulder joint includes a glenoid cavity, a humerus and a humeral ballattached to the humerus and positioned within the glenoid cavity, themethod comprising: positioning a patient on a surgical table; mounting asupport apparatus to the surgical table; attaching a first retractorsupport arm to the support apparatus; positioning the first retractorsupport arm about the shoulder joint; attaching a second retractorsupport arm to the first retractor support arm such that the first andsecond retractor support arms provide access to the shoulder joint;incising the flesh of the patient about the shoulder joint; attaching afirst retractor having a first retractor blade to the first retractorsupport arm; attaching a second retractor having a second retractorblade to the second retractor support arm; positioning the first andsecond retractor blade within the incision; and retracting the flesh ofthe patient from the shoulder joint with the first and second retractorblades such that the shoulder joint is exposed.
 35. The method of claim34 and further comprising: disposing a humerus retractor on the firstsupport arm; and positioning the humerus retractor about the humeruswith a mechanical system within the humerus retractor.
 36. The method ofclaim 35 and further comprising separating the humeral ball from thehumerus.
 37. The method of claim 36 and further comprising sawing thehumeral ball from the humerus.
 38. The method of claim 36 and furthercomprising: hollowing a cavity into a freshly separated surface of thehumerus; disposing a stem having a ball attached thereto into the cavityin the humerus; and securing the stem within the cavity such that theball is fixed into position on the humerus.
 39. The method of claim 38and further comprising securing an insert within the glenoid cavity. 40.The method of claim 39 and farther comprising disposing the ballattached to the humerus within the insert secured within the glenoidcavity.
 41. The method of claim 35 wherein the positioning of thehumerus retractor further comprises: manipulating the mechanical system,wherein the mechanical system comprises a rack and pinion system, toadjust a longitudinal position of the humerus retractor blade such thatthe humerus retractor blade including a substantially flat portion, anarcuate end portion and an aperture therein, extends beyond a medialsurface of the humerus; manipulating a vertical adjustment system,wherein the vertical adjustment system comprises an articulated joint,to lower the arcuate end portion of the humerus retractor blade belowthe humerus such that the aperture within the humerus retractor blade isvertically aligned with the humerus; and manipulating the rack andpinion system of the mechanical system such that the humerus retractorblade including the aperture engages the humerus.
 42. The method ofclaim 41 and further comprising retracting the humerus laterally fromthe glenoid cavity, wherein the lateral retraction comprisesmanipulating the rack and pinion system of the mechanical system todisplace the humeral head from the glenoid cavity to provide accessthereto.
 43. The method of claim 42 and further comprising: disengaginga pawl from the rack and pinion system; and manipulating the rack andpinion system such that the humeral ball attached to the humerus ispositioned proximate the glenoid cavity.
 44. The method of claim 43 andfurther comprising: manipulating the articulated joint such that thehumeral ball is juxtaposed to the glenoid cavity; and manipulating therack and pinion system to disengage the humerus retractor blade from thehumerus.
 45. The method of claim 44 and further comprising inserting thehumeral ball within the glenoid cavity.
 46. The method of claim 34 andwherein the positioning of the first support arm comprises: disposingthe first support arm, the first support arm being generally J-shaped,within the retractor support mounted to a surgical table; and rotatingthe retractor support mounted to the surgical table to position thefirst support arm about the shoulder joint.
 47. The method of claim 46and wherein the attaching of the second support arm to the first supportarm further comprises disposing a plurality of pegs within the secondsupport arm into a plurality of apertures within the generally J-shapedfirst support arm and wherein the second support arm is generallyT-shaped such that the generally J-shaped first support arm and thegenerally T-shaped second support arm provide access to the surgicalsite.
 48. The method of claim 34 wherein the retraction of the flesh bythe first and second retractors comprises: manipulating a mechanicalsystem within each of the first and second retractors, wherein eachmechanical system comprises a rack and pinion system, to adjust alongitudinal position of first and second retractor blades such that thefirst and second retractor blades are positioned above the incision;manipulating a vertical adjustment system within each of the first andsecond retractors, wherein each vertical adjustment system comprises anarticulated joint, to lower the first and second retractor blades intothe incision; and manipulating each rack and pinion system of themechanical system of the first and second retractors such that thesevered flesh is retracted from the incision to expose the shoulderjoint.